The densest sober crowds on Earth. Bonds here form on shared purpose alone.
Four numbers decide what a crowd does: how tightly it is packed, how loud it is, how fast alcohol arrives, and how much attention is available for the people beside you. Everything below is either a published figure or derived from one.
Pilgrimages are the largest gatherings humans produce. The 2025 Maha Kumbh Mela recorded around 660 million visits over 45 days; Arbaeen draws some 21 million to Karbala; the Hajj brought 1.83 million pilgrims to Mecca in 2024. At ground level the crowd runs about 2.5 people per square metre, Fruin grade F.
They are also entirely dry, which makes them the cleanest test of what a crowd does without chemical assistance. The answer is: a great deal. The model records 12.97 encounters per person per hour and 481 lasting ties — comparable to a nightclub, with a mean blood alcohol of exactly zero.
The room is quiet, so speech reaches 2.1 metres, and roughly half the crowd's attention is on the rite rather than on their neighbours. What is left is enough. Shared purpose does most of what alcohol and volume are hired to do in a venue, and does it more reliably.
Measured output from a standard run: 1,200 people, 4 hours of venue time, fixed seed, no parameter overrides. Every room on this site is run under identical conditions, so these figures are a like-for-like comparison rather than a set of individually flattering runs.
The crowd is a simulation and is presented as one. What is not invented are its constants: walking speed against density, the proxemic zones, the collapse of speech range with noise, the Widmark blood-alcohol curve and the conversational group limit all come from published work, cited above and listed in full in the engine.
Every gathering below is modelled as this kind of room. Attendance figures are published numbers for the period stated.
The Maha Kumbh Mela at Prayagraj in 2025, with around 660 million visits recorded over 45 days according to the Uttar Pradesh state government.
Around 2.5 people per square metre at ground level — Fruin grade F, where crowd force propagates. This is why crowd management at these events is a serious engineering discipline.
In this model, yes and substantially. A completely dry pilgrimage produces an encounter rate and tie count comparable to a nightclub, because it is quiet enough for speech to carry and nobody is rushing through.
Each person is one cell with a position, a body mass, a Widmark distribution ratio, an openness trait and a reserve of energy. They walk at the speed the local density allows, drink at the rate the room serves, and when two of them stay within speech range long enough, a bond forms. Most bonds are nothing.
What separates an encounter that creates something from one that does not is whether it bridges two groups that were not previously connected. A tie inside an existing group mostly restates what that group already knows; a tie across a gap carries information neither side had. That distinction is Granovetter's, and it is the mechanic the whole model turns on.
One parameter has no citation and should be read as an assumption: attention, the share of a person available to whoever is beside them rather than to a stage, a road or a rite. It is the variable that separates a street crossing from a dancefloor at similar density, and it is the one this model asserts rather than borrows.
